es6 rename keys in object array

Question

I have a sample array

const countries = [
    {"id": 1, "name": "Afghanistan"},
    {"id": 2, "name": "Albania"},
    {"id": 3, "name": "Algeria"},
    {"id": 4, "name": "American Samoa"}
];

How can i change the keys from id and name to label and value like this in es6?

const countries = [
    {"label": 1, "value": "Afghanistan"},
    {"label": 2, "value": "Albania"},
    {"label": 3, "value": "Algeria"},
    {"label": 4, "value": "American Samoa"}
];

Answer 1

Use .map to transform one array into another, and destructure the arguments for the least syntax noise:

const countries = [
    {"id": 1, "name": "Afghanistan"},
    {"id": 2, "name": "Albania"},
    {"id": 3, "name": "Algeria"},
    {"id": 4, "name": "American Samoa"}
];
const transformed = countries.map(({ id, name }) => ({ label: id, value: name }));
console.log(transformed);

You could also transform to the new property names in the arguments themselves, if you wanted:

const countries = [
    {"id": 1, "name": "Afghanistan"},
    {"id": 2, "name": "Albania"},
    {"id": 3, "name": "Algeria"},
    {"id": 4, "name": "American Samoa"}
];
const transformed = countries.map(({ id: label, name: value }) => ({ label, value }));
console.log(transformed);